Download Transport Systems in Plants Learning Outcomes Surface Area to

National 5 Biology – Multicellular Organisms – Need For Transport
Transport Systems in Plants
Xylem, phloem, lignin, companion cell, sieve plates, transpiration,
photometer, stomata, turgid, flaccid
Learning Outcomes
You will be able to:

Explain the need for transport systems in multicellular organism

Explain why plants require a transport system for water

State the name for the movement of water through a plant

State the structures involved in the transport of water in plants

Describe the structure and function of xylem

Describe the function of guard cells

Name environmental factors which increase the rate of transpiration in
plants

Explain why plants require a transport system for sugar

State the structure involved in the transport of sugar in plants
Surface Area to Volume Ratio
A unicellular organism has a large surface area in relation to its volume;
a multicellular organism has a smaller surface area in relation to its
volume.
Unicellular organisms gain raw materials for chemical reactions through
diffusion. They have a large surface area to volume ratio and the raw
materials diffuse quickly to all areas of a cell.
Multicellular organisms have a small surface area to volume ratio.
Diffusion cannot occur fast enough to supply the raw materials to the
whole cell. Therefore they have transport systems to carry the raw
materials to their sites of diffusion.
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National 5 Biology – Multicellular Organisms – Need For Transport
Learning Activity 1
1. Name two essential materials which cells require.
2. Name two two exampless of waste productss produced by cells.
3. Name the processes responsible for transporting these substances into
and out of cells.
4. Insert and complete the ‘Surface Area: Volume’ worksheet.
5. Explain why a large animal requires a transport system to deliver essential
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materials to cells.
Transport Systems in a Plant
Unlike animals, plants do not have a circulatory system where a heart
pumps blood to organs in blood vessels. Plants have two different types
of 'transport' tissue.,.
Instead, plants have a transport system of with two types of vessels,
Xylem xylem which transports water and solutes mineral salts from the
roots to the leaves and phloem which transports food sugars (food) from
the leaves to the rest of the plant.
Transport of Water - Xylem
Plants require water for photosynthesis. Water and soil minerals are absorbed
through root hair cells and transported up the plant to the leaves in xylem.
Xylem vessels carry water and dissolved minerals up from
the roots and are found throughout the plant in the root,
stem and leaves. They are non-living vessels composed of
xylem cells stacked end to end to form hollow tubes. The
end walls of the xylem cells disintegrate to leave hollow
tubes while the side walls become strengthened with rings or
spirals of lignin.
The lignin provides support and allows the vessels to withstand pressure
changes as the water moves up through the plant.
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lignin
National 5 Biology – Multicellular Organisms – Need For Transport
You can demonstrate the movement of
water and the location of xylem vessels by
dipping the stem of a stick of celery stick
into a coloured solution such as Eosin or
food colouring. When eating celery the
xylem is the annoying stringy bit!
Transport of Sugar (food) - Phloem
Sugar is produced in the leaves during photosynthesis. It must be transported
all around the plant in phloem vessels to provide energy for growth and repair.
Unlike xylem cells, phloem cells must be alive for them to transport sugar.
Phloem vessels carry glucose up and
down the plant. They are living vessels
composed of phloem cells stacked end to
sieve plate
phloem cell
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end to form cellular sieve tubes. The end
companion
walls of the phloem cells are perforated
cell
to form sieve plates. Companion cells
support the phloem vessels.
National 5 Biology – Multicellular Organisms – Need For Transport
Learning Activity 1
1. Insert and complete the ‘Transport System in Plants’ worksheet into
your workbook.
2. Collect the experiment card ‘Transport of Water’ follow the instructions
on the card to observe the movement of water through xylem in celery.
Transpiration
Water is used for photosynthesis in the leaves of a plant. Water evaporates
out of the leaf in a process called transpiration.
Transpiration is the loss of water from parts of the plant above the ground
due to evaporation. This process is the equivalent to sweating in animals; hence
it helps to cool down the plant. Transpiration takes place primarily through the
stomata (pore on the underside of leaves). The rate of transpiration is
affected by many factors such as: temperature, wind-intensity, humidity, and
light-intensity. The rate of transpiration is measured using an instrument
called a potometer
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National 5 Biology – Multicellular Organisms – Need For Transport
Learning Activity 1
1.
Insert and complete ‘Transpiration’ diagram and paste into your workbook.
2. Arrange the following parts to show the direction taken by water molecules:

Xylem

Root hair

Cortex

Soil

Leaves
3. Insert and complete ‘Transpiration Experiments’ diagram and paste into your
workbook.
Leaf Structure
Leaves are the main site of photosynthesis within a plant. They contain
different types of cells to allow them to photosynthesise efficiently.
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National 5 Biology – Multicellular Organisms – Need For Transport
Stomata
The actions of the stomata are closely related to the hydration of the plant.
The stomata pores are regulated by surrounding guard cells which regulate the
rate of transpiration. When guard cells become turgid they cause stomata to
open allowing water to evaporate. When the plant has become dehydrated (or
when the plant is not photosynthesizing such as at night) guard cells loose water
and become flaccid causing stomata to close. The rate of transpiration can be
directly related to whether the stomata are open or closed.
Guard cells turgid
Guard cells flaccid
(swollen)
(shrunken)
Learning Activity 2
1. Collect and label the diagram ‘Leaf Structure’ and paste into your workbook.
2. Copy and complete the table below, use class resources to help you complete
the table.
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National 5 Biology – Multicellular Organisms – Need For Transport
Part
Function
Upper Epidermis
Mesophyll layer
Lower epidermis
Stoma
Guard cells
Moist air space
3. Copy and label the diagram of the open and closed stomata.
4. Describe the structure of a guard cell.
5. State what happens to stomata:

during the day

during the night.
6. Explain these changes in terms of turgor of the guard cells.
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National 5 Biology – Multicellular Organisms – Need For Transport
The Heart
Heart, atrium, ventricle, vena cava, pulmonary artery, pulmonary vein,
aorta, atrio-ventricular valve, semi-lunar valve, artery, capillary, vein
Learning Outcomes
You will be able to:

Describe the structure of the heart to include the names of the chambers,
the blood vessels entering and leaving the heart

Describe the position and the function of valves in the heart

Describe the pathway of blood through the heart, lungs and body

Describe the structure and function of arteries, veins and capillaries

Explain how the structure of a capillary network is related to its function
The Circulatory System
The circulatory system is made up of the heart (a muscular pump) and the blood
vessels (a system of tubes) which carry blood to all parts of the body.
Nutrients, oxygen, carbon dioxide and hormones are all transported in the
blood.
The Heart
The heart is a muscular pump that is divided into four chambers. The two upper
chambers are the right atrium and the left atrium. The two lower chambers are
the right ventricle and the left ventricle. The wall of the left ventricle is thick
because it pumps blood all-round the body whereas the wall of the right
ventricle is less thick as it only pumps blood to the lungs. The right and left
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National 5 Biology – Multicellular Organisms – Need For Transport
atrio-ventricular valves separate the upper and lower chambers of the heart.
The presence of valves ensures that blood flows in one direction only.
Semi-lunar valves
Right atrium
Left atrium
Atrio ventricular valve
Y
Atrio
ventricular valve
Left ventricle
Right ventricle
Circulation of Blood through the Heart
Deoxygenated blood from all parts of the body is brought to the right atrium by
two main veins called the vena cava. This blood passes into the right ventricle
and is then carried away from the heart by the pulmonary artery, which divides
into two branches, taking blood to the right and left lung. The blood becomes
oxygenated (picks up oxygen) in the lungs and returns to the heart through the
pulmonary veins and enters the left atrium. The blood flows from the left
atrium into the left ventricle and then leaves the heart through the aorta the
largest artery in the body. The pulmonary artery and the aorta have valves
called semi-lunar valves. When the ventricles contract the valves open allowing
blood to flow into these blood vessels. The valves will then close and prevent
blood flowing back into the heart.
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National 5 Biology – Multicellular Organisms – Need For Transport
Heart Valves
There are four valves associated with the
heart. The valves that separate the atria
from the ventricles are called AV valves
(atrio-ventricular valves). Then there are the
valves that separate the ventricles from the
arteries leaving the heart which are known as
SL valves (semi-lunar valves).
Learning Activity 1
1. Insert Insert the ‘Heart Diagram’ and label. the chambers of the heart
1.2.
How many chambers does a heart have?
2.3.
3.4.
Write down the names of :

the smaller (top) chambers

the larger (bottom) chambers
Draw circles aroundLabel the heart valvesvalves on your Heart Diagram
and state their function, and make a key for this.
4.5.
State where blood is pumped to from the:

left ventricle

right ventricle.
5.6.
Explain why the muscle wall of the left ventricle is thicker than the
right ventricle wall.
On your Heart Diagram,
 shade the chambers and vessels which deal with deoxygenated
blood returning from the body and going to the lungs in blue.
 On your Heart Diagram, shade the chambers and vessels which
deal with oxygenated blood returning from the lungs and going
to the body in red.


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include a key
add arrows to show the path that blood takes through the heart.
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National 5 Biology – Multicellular Organisms – Need For Transport
The Hearts own Blood Supply
Heart muscle cells need their own
direct blood supply in order to
function. If they were to draw oxygen
from the blood that passes through
their chambers, the right side of the
heart would die. The coronary
arteries supply the heart muscle cells
with food and oxygen, so they can
make energy by the process of
respiration. Carbon dioxide and other
waste are removed from the muscle
cells by the coronary veins.
The coronary arteries are found on
the outside of the heart and so can be
relatively easily replaced in bi-pass
surgery.
Coronary Artery
Learning Activity 2
1. Insert and complete the ‘Coronary Artery’ diagram by labelling the coronary
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hat would happen to the heart if this artery became blocked?
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artery.
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
pulmonary artery

pulmonary vein
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National 5 Biology – Multicellular Organisms – Need For Transport
3.4.

aorta

vena cava
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13. Copy & complete the table below :
Blood Vessel
Pulmonary
Artery
Collects Blood
Takes Blood
From
To
Heart
Level of CO 2
Lungs
Aorta
Level of O2
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Higher
Lower High
Vena Cava
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Lungs
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Heart
Pulmonary
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Low
Vein
Pulmonary
Vein
Aorta
Vena Cava
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Blood Vessels
Blood is carried by blood vessels to all cells in the body. The three main types
of blood vessels are the arteries, veins and capillaries.
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National 5 Biology – Multicellular Organisms – Need For Transport
Arteries
Arteries have thick muscular walls to withstand the high pressure of blood
coming from the heart. Each time the heart beats, the contraction of the walls
of the ventricle forces blood along the arteries at high pressure. This can be
felt as a pulse in an artery. Arteries carry oxygenated blood with the exception
of the pulmonary artery.
Veins
Veins also have muscular walls but the walls are thinner than that of the
arteries since the blood flowing through veins is at a lower pressure than that
of arteries. The central cavity (lumen) is wider than that of an artery. This
helps to reduce resistance to the flow of blood along a vein. Veins have valves to
prevent blood flowing back along the vessel (backflow). Veins usually carry
deoxygenated blood with the exception of the pulmonary vein.
Capillaries
Capillaries are tiny blood vessels whose walls are only one cell thick. They are
referred to as exchange vessels since all exchanges of materials between blood
and living tissues takes place through their thin walls e.g. oxygen diffusing from
the blood into the tissues, carbon dioxide diffusing from the tissue cells into
the blood.
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National 5 Biology – Multicellular Organisms – Need For Transport
Learning Activity 3
1. Insert and complete the ‘blood vessels’ diagram into your workbook.
2. Copy & complete the flow chart by entering the names of the types of
vessels:
from heart
to heart
Transport of Substances in the Blood
Blood, red blood cell, white blood cell, platelet, haemoglobin, plasma,
biconcave, oxyhaemoglobin
Learning Outcomes
You will be able to:

State what is carried in the blood

Explain the function of haemoglobin

Explain the need for iron in the diet and health problems when there is a
lack of iron
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National 5 Biology – Multicellular Organisms – Need For Transport
Blood
Blood consists of straw coloured watery liquid called plasma, red blood cells and
white blood cells.
Plasma transports blood cells and dissolved materials such as glucose, amino
acids, the waste material, urea, and some carbon dioxide around the body.
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Red blood cells are specialised to carry oxygen. They are very small and
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flexible, allowing them to squeeze through the smallest blood capillaries. They
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3
are also very numerous (5.5 million per mm of blood). They have a biconcave
disc shape to increase the surface area for oxygen uptake and no nucleus which
allows them to be packed full of the red, oxygen-carrying pigment, haemoglobin.
White blood cells play a role in defence of the organism against infection.
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What to do
1.
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Haemoglobin
Haemoglobin is a respiratory pigment which readily combines (associates) with
oxygen to form oxyhaemoglobin when the oxygen concentration of surrounding
cells is high e.g. in the capillaries of the alveoli. Haemoglobin can rapidly release
(dissociate) oxygen from oxyhaemoglobin when the oxygen concentration of
surrounding cells is low e.g. in capillaries next to respiring cells.
This reversible reaction can be summarised in the form of a chemical equation.
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(in lungs)
Haemoglobin +
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Oxygen
Oxyhaemoglobin
National 5 Biology – Multicellular Organisms – Need For Transport
(in tissues)
Copy & complete the diagram below, which shows the
different parts of blood:
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National 5 Biology – Multicellular Organisms – Need For Transport
2.
Read “Composition of blood” in SG Biology:
BLUE BOOK
page 160
Learning Activity 1
1. Insert the ‘Red Blood Cell’ diagram into your notes.
2. Complete the following table to describe the function of each of the
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following structures of red blood cells.
Structure
Function
Biconcave disc
Small and flexible
Extremely numerous
Contains no nucleus
Cytoplasm contains
haemoglobin
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3. Insert and complete the ‘Haemoglobin Note’ into your workbook.
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National 5 Biology – Multicellular Organisms – Need For Transport
Challenge Task
Explain the need for IRON in the diet and health problems that
can occur when there is a lack of iron.
The Respiratory System
Trachea, bronchi, bronchioles, alveoli, lungs, diaphragm, cilia,
cartilage, mucus
Learning Outcomes
You will be able to:

Describe the structure and function of the lungs

Explain the function of the rings of cartilage in the trachea

Describe the function of cilia and mucus in the trachea

Describe gas exchange within the alveoli

Explain how the structure of the lungs is related to their function
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National 5 Biology – Multicellular Organisms – Need For Transport
The Respiratory System
Gas exchange takes place in the lungs. The lungs are sponge-like because they
consist of millions of tiny air sacs called alveoli (singular: alveolus). When air is
breathed in, it passes down the trachea or windpipe, into the right and left
bronchus, which further branch into smaller tubes called bronchioles and then
into the alveoli. The bottom of the lung cavity is separated from the rest of the
body by a muscle called the diaphragm. The lungs are protected at the front
and rear by ribs.
Learning Activity 1
1. Collect and complete the ‘Lung Diagram’ by labelling your diagram with the
following:
diaphragm
lung
bronchus
bronchiole
intercostal muscle
trachea
heart
rib
nose
Structure of Air Passages
The trachea, bronchi and bronchioles are all
lined with rings of cartilage, which perform
a similar function to lignin in xylem. They
strengthen the air passages and ensure
that they stay open in situations where
external pressure increases such as deep
sea diving or when an owl’s neck is twisted.
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National 5 Biology – Multicellular Organisms – Need For Transport
When we breathe in, we inhale air
containing dirt, dust and microorganisms and our lungs have a
system
to
deal
with
these
unwanted contaminants. The walls
of the respiratory tubes are lined
with two types of cells. Goblet
cells produce sticky mucus and
the epithelial cells have hair like
structures called cilia on their
surface. The mucus traps any
particle that lands on it and the
cilia beat upwards in a wave like
motion (think Mexican wave) and
push the mucus up the airways
until it reaches the mouth and is
swallowed.
Alveoli
The alveoli are the swellings at the end of the respiratory tubes and are the
site of gas exchange.
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They are so numerous that they
provide a very large surface
area for gas exchange. The total
internal surface area of the lungs
is approximately 90m2 (The size
of a tennis court). The lining of
each alveolus is very thin allowing
easy diffusion of oxygen into the
blood. The walls of the alveoli are
moist to allow oxygen to dissolve
before diffusion. A network of
blood capillaries surrounds the
alveoli allowing an exchange of
gases to take place.
Blood arriving in the lungs is deoxygenated i.e. contains a low concentration of
oxygen. The air breathed into the alveolus contains a high level of oxygen, so
oxygen diffuses from a high concentration in the alveolus to a low concentration
in the blood and the blood becomes oxygenated. Deoxygenated blood contains
higher levels of carbon dioxide than the air in the alveolus, so carbon dioxide
diffuses from a higher concentration in the blood to a lower concentration in
the alveolus. The carbon dioxide is then breathed out of the lungs (exhaled).
Learning Activity 2
1. State the advantage of having large numbers of alveoli in the lungs.
2. Describe the structure of an alveolus (pl. alveoli), with reference to the:
-
Lining
-
surrounding blood vessels
-
distance from the surrounding blood vessels.
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3. Describe the composition, in terms of O2 and CO2 concentrations, of:
-
oxygenated blood
-
deoxygenated blood.
4. Describe the process of gas exchange in the lungs, with reference to the:
-
type of blood arriving
-
blood vessel which supplies the blood
-
exact location of gas exchange
-
film of moisture
-
direction in which the O2 is transported
-
process involved in the transport of O2
-
direction in which the CO2 is transported
-
blood vessel which carries the oxygenated blood away.
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5. Copy and complete the table below showing the 4 main features which make
lungs efficient gas exchange surfaces.
Feature of lungs
Function
large surface area
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alveolar lining has moist film
allows rapid diffusion of oxygen
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allows rapid transport of oxygen to body cells
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2.6.
Insert and complete the ‘Gas Exchange’ diagram into your notes.
The Digestive System
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National 5 Biology – Multicellular Organisms – Need For Transport
Digestive system, alimentary canal, peristalsis, small intestine, villi,
lacteal
Learning Outcomes
You will be able to:

State the function of the digestive system

Name the parts of the digestive system and give their function

Describe the process of peristalsis

Explain how the structure of the small intestine is related to its function

State where glucose, amino acids, fatty acids and glycerol are absorbed
within the villi
The Digestive System
The digestive system is
responsible for the breakdown
of large insoluble food molecules
into smaller soluble molecules
which can be absorbed into the
bloodstream. The alimentary
canal is the name for the tube
that runs from the mouth to the
anus. As insoluble molecules of
food pass along this muscular
tube they are broken down to a
soluble state by digestive
enzymes. The salivary glands,
liver and pancreas, which are
connected by ducts to the alimentary canal,
are described as associated organs.
Peristalsis
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From the moment food is swallowed, it gets pushed along this tube by a series
of sequential muscular contractions known as peristalsis. Part of the gut wall is
composed of circular muscle. When this contracts behind a portion of food, the
central hole of the tube becomes narrower and the food is pushed along. At the
same time the circular muscle in front of the food becomes relaxed allowing the
central hole to enlarge and let the food slip along easily.
The final stages of digestion and the absorption of nutrients take place in the
small intestine, and it is perfectly designed to perform this function.
Learning Activity 1
1. Collect and complete the ‘Human Digestive System’ diagram.
2. Describe how food moves down the oesophagus, with reference to the:
-
state of the muscle behind the food
-
state of the muscle in front of the food
-
direction of movement.
3. Insert and complete the ‘Peristalsis’ diagram into your notes.
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Small Intestine
When the partially digested food enters the small intestine from the stomach,
it is mixed with another enzymes which complete the process of digestion. Fats
are broken down The pancreas produces lipase which promotes the breakdown
of fats into fatty acids & glycerol., carbohydrates are broken down to the
simple sugar, glucose, and proteins are completely broken down to amino acids.
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National 5 Biology – Multicellular Organisms – Need For Transport
These small molecules are absorbed
into the bloodstream through the
specially adapted lining of the small
intestine.
Villi
There are three common themes
for any surface where there is the
exchange of materials:
1. Large surface area (for diffusion)
2. Walls are only one cell thick (short diffusion distance)
3. There is a good blood supply (to remove the diffusing substance and thus
maintaining the concentration gradient.
The presence of millions of finger like projections called villi in the small
intestine fulfils all of these criteria.
If villi are finger like projections, then a structure called the lacteal could
represent the bone of the finger. The lacteal is where the products of fat
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National 5 Biology – Multicellular Organisms – Need For Transport
digestion are absorbed from the small intestine. The products of protein and
carbohydrate digestion both get absorbed into the capillary of the villus.
4. ___________________________________________________________ L Formatted: Left,
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numbering, Tab stops: 16.75 cm,
Left,Leader: ___
earning Activity 2
5.1. _____________________________________________________________________ S Formatted: List Paragraph, Left,
tate the main function of the small intestine.
1.2.______________________________________________________________________ G
ive 3 reasons whyState how the small intestine is structurally suited to
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+ Indent at: 0.63 cm, Tab stops:
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absorb the products of digestion.
2.3. _____________________________________________________________________ N
ame the structure found in the small intestine which is responsible for the
absorption of the products of digestion.
4. Copy and complete the table below
Food Group
Product(s) of Digestion
Part of Villus that absorbs it
5. Insert and complete the ‘Structure Of Aof a Villus’ diagram into your
notes.
The Effects of Lifestyle Choices
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National 5 Biology – Multicellular Organisms – Need For Transport
Learning Outcomes
You will be able to:

Explain how poor diet and lack of exercise can affect transport and
exchange systems thus causing disease.

Explain how smoking and drinking excess alcohol can affect transport and
exchange systems, and how this can lead to disease
Health and well-being are affected by the lifestyle choices, heredity and
the environment.

Choose a condition from the list and find out:
1. What part of the body is affected by the condition?
2. What causes the condition?
3. What are the symptoms of the condition?
4. What are the lifestyle choices that affect the condition?
1.5.
How can this condition be treated?
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12 pt
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Based on the research you have done state your opinion on
whether or not this condition should be treated for free under the NHS with
supporting argument.
Present your information as a brief report to the rest of the
class.
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bullets or numbering
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bullets or numbering, Tab stops:
3.04 cm, Left + Not at 1.59 cm +
2.22 cm
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National 5 Biology – Multicellular Organisms – Need For Transport
Conditions

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Asthma, Bronchitis, Emphysema, Pneumonia, Lung cancer, Coronary
Heart Disease, Stroke, Constipation, Stomach ulcers, Diarrhoea,
IBS, Crohn’s Disease, Coeliac Disease, Cirrhosis of the liver, Type
2 Diabetes, Obesity.7.
What is the function of white blood
cells?
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8.
Draw a diagram of a white blood cell.
9.
Stick the “Haemoglobin Note” from your pack into your
notes.
10. Read “Function of haemoglobin” in SG Biology:
BLUE BOOK
page 161 and Figure 17.22
YELLOW BOOK
page 139 and Figure 17.17
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National 5 Biology – Multicellular Organisms – Need For Transport
1.
Read the Haemoglobin Note and use the information to
complete the equation at the bottom of it.
2. You
may now be given an opportunity to look at prepared and
stained blood slides.
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14 pt
Criteria:
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 Show that you have learned something for each of the 4 point.
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1.State your opinion with supporting argument and be prepared to take questions.s.
2.Use a style suitable for your audience.
3.Prove that the information you present is reliable by making a list of References to
include with your presentation. This must include the name and author of all the
books you use and the names of all the websites you use with the dates you access
them.
 Use the format given by your teacher.
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